This text aims to demystify all of the undocumented features of the Stacker disk compression utility. Topics covered include: the secret to custom Stacker installation and setup; tips for worry-free compression of OS/2 data; advice on upgrading compressed drives to OS/2 2.1; late-breaking information on Stacker 3.1; details on the OS/2 CONFIG.SYS and other OS/2 system files; and how to use Stacker utilities such as UNSTACK, REMOVDRV, CONFIG, BOOT and REPORT. Chapter-ending reviews and a complete glossary are included. The author offers solutions to eight of the most common problems encountered by the Stac OS/2 tech support staff. Readers find out how to change the location of Stacker files, use Stacher with CD-ROM drives, repair damaged drives with AutoProtect and AutoRecovery, respond to error messages on OS/2 start-up, and remove write-protection of OS/2 drives. The text should enable the users to double their hard disk storage capacity.